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Alzheimer’s stages: How the disease progresses

Alzheimer’s disease tends to develop slowly and gradually worsens over several years. Eventually, Alzheimer’s disease affects most areas of your brain. Memory, thinking, judgment, language, problem-solving, personality and movement can all be affected by the disease.

There are five stages associated with Alzheimer’s disease. They include:

Dementia is a term used to describe a group of symptoms that affect intellectual and social abilities enough to interfere with daily function.

The five Alzheimer’s stages can help you understand what might happen. But it’s important to know that these stages are only rough generalizations. The disease is a continuous process. Each person has a different experience with Alzheimer’s and its symptoms.

Alzheimer’s disease begins long before any symptoms become apparent. This stage is called preclinical Alzheimer’s disease. It’s usually identified only in research settings. You and those around you won’t notice symptoms during this stage.

This stage of Alzheimer’s can last for years, possibly even decades. Although you won’t notice any changes, new imaging technologies of the brain can identify amyloid plaques and neurofibrillary tangles. The tangles develop when tau proteins change shape and organize into structures. These are hallmarks of Alzheimer’s disease.

The ability to identify these early changes is especially important for clinical trials. Ongoing trials are looking at whether treating people with preclinical Alzheimer’s may delay or slow the onset of symptoms. The imaging technologies also are important as new treatments are developed for Alzheimer’s disease.

Additional biomarkers have been identified for Alzheimer’s disease. These are found in blood samples and can indicate an increased risk of disease. These biomarkers can be used to support the diagnosis of Alzheimer’s disease, typically after symptoms appear.

Genetic tests also can tell you if you have a higher risk of Alzheimer’s disease, particularly early-onset Alzheimer’s disease. These tests aren’t recommended for everyone. You and your health care provider can discuss whether genetic testing might be helpful for you.

Newer imaging techniques, biomarkers and genetic tests will become more important as new treatments for Alzheimer’s disease are developed.

People with mild cognitive impairment have mild changes in their memory and thinking ability. These changes aren’t significant enough to affect work or relationships. People with MCI may have memory lapses when it comes to information that is usually easily remembered. This may include conversations, recent events or appointments.

People with MCI also may have trouble judging the amount of time needed for a task. They may have trouble judging the number or order of steps needed to complete a task. The ability to make sound decisions can become harder.

Not everyone with mild cognitive impairment has Alzheimer’s disease. MCI is often diagnosed based on a health care provider’s review of symptoms and professional judgment. But if necessary, the same procedures used to identify preclinical Alzheimer’s disease can help determine whether MCI is due to Alzheimer’s disease or something else.

Alzheimer’s disease is often diagnosed in the mild dementia stage. This is when it becomes clear to family and doctors that a person is having significant trouble with memory and thinking. The symptoms impact daily functioning.

In the mild dementia stage, people may experience:

During the moderate dementia stage of Alzheimer’s disease, people grow more confused and forgetful. They begin to need more help with daily activities and self-care.

People with the moderate dementia stage of Alzheimer’s disease may:

In the late stage of the disease, called severe dementia due to Alzheimer’s disease, mental function continues to decline. The disease also has a growing impact on movement and physical capabilities.

In late-stage severe dementia due to Alzheimer’s disease, people generally:

The rate of progression for Alzheimer’s disease varies widely. On average, people with Alzheimer’s disease live between three and 11 years after diagnosis. But some live 20 years or more. The degree of impairment at diagnosis can affect life expectancy. Untreated vascular risk factors such as hypertension are associated with a faster rate of progression of Alzheimer’s disease.

Pneumonia is a common cause of death because impaired swallowing allows food or beverages to enter the lungs, where an infection can begin. Other common causes of death include dehydration, malnutrition, falls and other infections.

© 1998-2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved.

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